I am looking for the most powerful trimmer. Should I get a Shindaiwa or Redmax? I know Shindaiwa has speed feed and starts really easy. A guy I know says he uses Redmax and they run around $400, but I have a backpack Shindaiwa that is really good, really powerful so I thought I would keep my Shindaiwa blower and add a Shindaiwa trimmer with speed feed. Thanks.